The self-insured employer appeals the compensation judge’s finding that the employee’s ankle injury arose out of her employment.  We affirm.

On September 17, 2011, Carol Kainz, the employee, was employed as a Licensed Practical Nurse (LPN) with Arrowhead Senior Living Community at the St. Michael’s Health and Rehabilitation Center, the employer, which was self-insured for workers’ compensation liability.  Her job duties as an LPN included dispensing medications, giving treatments and supervising certified nursing assistants.  The employer’s building where the employee worked included a nursing home and a rehabilitation center and consisted of two floors, a main floor and a basement.

On September 17, 2011, after dispensing medications to her assigned patients, the employee left the main floor to retrieve supplies from inside a locked cage in the basement.  The employee entered an interior stairwell from the main floor to the basement and descended down the first flight of steps onto a platform, then proceeded to the second flight of steps toward the basement landing.  The employee described the stairway as “kind of steep.”^[1]  While descending the second flight of stairs, the employee inverted and twisted her ankle, causing an avulsion fracture.  The employee hobbled down the remaining stairs, returned to the main floor using an elevator, reported the injury to her supervisor, and finished her shift after the supervisor wrapped her ankle.^[2]  The employee was treated for the fracture and missed work due to the injury from September 18 through November 7, 2011.

On November 15, 2011, the employee filed a claim petition seeking temporary total disability benefits and related medical expenses, reserving permanent partial disability benefits, and requesting a rehabilitation consultation.  The employer denied the entire claim in its answer filed on January 5, 2012, asserting that the employee’s injury did not arise out of and in the course of her employment.

The employee’s claims were heard by a compensation judge on July 31, 2012.  In his findings and order dated September 11, 2012, the judge found, in part, that the general public was excluded from using that stairway, that there were no hand rails on that portion of the stairway where the employee inverted and twisted her ankle, and that the employee caught herself from falling by steadying herself against the wall.  The judge concluded in Finding 14 that the “employee’s right ankle avulsion fracture arose out of employee’s employment with the employer St. Michael’s Health and Rehabilitation Center.”  The judge awarded temporary total disability benefits and medical expenses.  The employer appeals.

The Workers’ Compensation Court of Appeals must determine whether the findings of fact and order are clearly erroneous and unsupported by substantial evidence in view of the entire record as submitted.^[3]  Substantial evidence supports the findings if, in the context of the entire record, they are supported by evidence that a reasonable mind might accept as adequate.^[4]  Fact findings are clearly erroneous if the reviewing court, looking at the entire evidence, is left with a definite and firm conviction that a mistake has been committed.^[5]  Findings of fact should not be disturbed, even though the reviewing court might disagree with them, “unless they are clearly erroneous in the sense that they are manifestly contrary to the weight of the evidence or not reasonably supported by the evidence as a whole.”^[6]  Questions of law may be considered by the Workers’ Compensation Court of Appeals de novo.^[7]

As a general rule, workers’ compensation benefits are payable “in every case of personal injury . . . arising out of and in the course of employment without regard to the question of negligence.”^[8]  The phrase “in the course of” refers to the time, place, and circumstances of the incident causing the employee’s injury, while “arising out of” connotes a causal connection between the employee’s injury and the employment, although not necessarily in the sense of proximate cause.^[9]  The requisite causal connection “exists if the employment, by reason of its nature, obligations or incidents may reasonably be found to be the source of the injury-producing hazard.”^[10]

Here, the parties agree that the employee was engaged in the course and scope of her employment at the time of the injury.  The ultimate issue was whether the injury “arose out of” the employment with St. Michael’s Health and Rehabilitation Center.  The compensation judge analyzed the compensability of the claim using the “increased risk” test.  Under the increased risk test, the employee is required to show she was subjected to an increased risk from some activity or condition incidental to her employment for injury than the risk borne by the general public.^[11]  The increased risk test, however, is not the only test used in Minnesota to analyze the arising out of element.^[12]

The employer argues that the employee sustained an idiopathic injury, and therefore the injury cannot be considered to arise out of her employment.  This court noted in Dykhoff, however, that there is a difference between “unexplained” injury cases and “idiopathic” injury cases.  “[U]nexplained-fall cases begin with a completely neutral origin of the mishap, while idiopathic fall cases begin with an origin which is admittedly personal and which therefore requires some affirmative employment contribution to offset the . . . showing of personal origin.”^[13]  As in Duchene v. Aqua City Irrigation, where the cause of the employee’s knee injury was unknown,^[14] there was no evidence in this case that the employee’s ankle injury arose from a non-work-related condition or activities personal to her.

In Dykhoff, this court stated that neither the increased risk test nor the positional risk test will be applicable in every case.^[15]  The “arising out of” and “in the course of” requirements “are elements of a single test of work-connection.”^[16]  The “proper analysis of compensability requires the balancing of both the ‘arising out of’ and ‘in the course of’ elements to determine whether, on the facts of each case, there is a sufficient ‘work-connection.’”^[17]  Determining whether the requisite causal connection exists is generally a question of fact for the compensation judge.^[18]  In essence, it is a question of detail, unique to each case, where various considerations must be weighed, and no absolute rule can be distinguished.^[19]

In most cases, an employee is covered by the workers’ compensation act “while engaged in, on, or about the premises where the employee’s services require the employee’s presence as a part of that service at the time of the injury . . . .”^[20]  “An activity is ‘in the course of employment’ if it occurs while the employee is fulfilling work duties or is engaged in activities reasonably incidental to his or her particular employment.”^[21]  In this case, the “in the course of” element is strong.  There is no dispute that the employee’s ankle injury occurred on the stairway of the employer’s building when she was retrieving supplies for work during her work shift.  The employee testified that the stairway was “kind of steep.”  Generally, “[a]s a matter of law, an injury which occurs during working hours and on the employer’s premises, even if it could have as easily occurred elsewhere, is compensable.”^[22]

Given the strength of the “in the course of” element from the facts in this case and the unexplained nature of the employee’s injury, the compensation judge did not err by finding that the employee’s ankle injury arose out of and the course of her employment.  We find substantial evidence supports the compensation judge’s determination that the employee’s injury arose out of and in the course and scope of employment, and we affirm on this issue.

Based on our decision above, the discrepancies between the employee’s testimony and the judge’s findings regarding the general public’s use of the stairway,^[23] the length of the handrails,^[24] and whether the employee steadied herself against a wall,^[25] do not change the determination of this case on review.

I concur in the result reached by the majority.